The present invention relates to arrangements for supplying photosensitive sheets unexposed to ambient light to a handling machine in general, and more particularly to an arrangement for supplying X-ray films to film unloading and loading apparatus in a manner which prevents ambient light from reaching the films.
There are already known various arrangements for supplying X-ray films to an unloading and loading apparatus which removes X-ray exposed films from cassettes and inserts new X-ray films into such cassettes for future use. One of the conventional loading and unloading machines includes a plurality of channel members which define respective channels for receiving storage receptacles containing stacks of X-ray films of different sizes. Each of the channel members is equipped with withdrawing means which are operative for withdrawing the X-ray films one after the other from the respective receptacles, after an opening of the respective receptacle, which has previously been closed by a lid, is uncovered or opened.
This construction was disclosed, for instance, in the published German patent application No. DE-OS 26 07 876. In this construction of the unloading and loading machine for X-ray film cassettes, storage receptacles having different sizes corresponding to the sizes of the X-ray films accommodated therein can be introduced, in a drawer-like fashion, into their respective channels. After the introduction of the respective storage receptacle into its associated channel, a drive of friction rollers is energized, so that such friction rollers open the withdrawing opening of the storage receptacle. Once the opening is uncovered, the withdrawing means of the machine is able to engage and withdraw the respectively uppermost X-ray film from the stack of films contained in the respective storage receptacle.
Experience with these drawer-like storage receptacles has shown that they are very prone to malfunction. So, for instance, the lid for the withdrawing opening can become stuck and cannot be sufficiently opened, or the lid is not fully closed during a premature removal of the storage container from the channel, so that the films remaining in the storage container become exposed to ambient light and thus usually damaged or destroyed.